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Full text of "Alaskan glacier studies of the National Geographic Society in the Yakutat Bay, Prince William Sound and lower Copper River regions"

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296                                ALASKAN GLACIEB STUDIES
the 882 foot basin opposite and below Brilliant Glacier, (2) another opposite and below Miner's River, (8) a third near Siwash Bay, (4) a fourth near Olsen Island (5) with unconsumed swells between where the ice rose after its plunge, perhaps because a cross current ran athwart its course where tributaries entered.
Above sea level, in Unakwik Inlet, deposits of glacial origin are inconspicuous, usually forming only a veneer of glacial till on some of the mountain slopes, and the coarse gravel fans, where the streams from Brilliant, Ranney and other glaciers enter the fiord,
East of Unakwik Inlet the mouths of Wells and Long Bays (PL XCIII) are 1404 and 852 feet deep respectively. The fiords between, north of Fairmount and Glacier Islands, are 288 to 420 feet deep. Wells and Long Bays contain no tidal glaciers at present, but were undoubtedly sculptured profoundly by the former ice tongues in them, which were tributary to the ancient ice sheet of Prince William Sound.
Eaglek Bay, extending parallel to Unakwik Inlet just west of Pt. Pellew, is only 5J miles in length. Eaglek Glacier, a small ice tongue, terminating half a mile from the head of the bay, was evidently once a tributary of the Prince William Sound ice sheet, for the sides of Eaglek Bay (896 feet deep) bear evidence of glacial erosion.
Esther Passage is a narrow channel between Esther Island and the mainland, connecting the east side of Port Wells with Prince WiUiam Sound, It has a length of about twelve miles, a width of from less than a quarter of a mile to a mile and a quarter, and is very sinuous in outline. The southward-trendmg eastern part of the passage has been notably modified by glaciation. Its depth, 142 feet, near where a glaciated valley comes in from the north, and 854 feet at the mouth, where it enters Prince William Sound, seems to be due to glacial erosion. Between these points is a place 552 feet deep, probably representing a glacial rock basin. The western part, which has a depth of 66 feet where it enters Port Wells, has not been much modified by glaciation.
General Description. West of Unakwik Inlet is Port Wells, which is the westernmost of the fiords entering Prince William Sound, and one of the largest fiords tributary to that body of water. Port Wells has two branches, College Fiord and Harriman Fiord, the latter coming in from the northwest, the former from the northeast. College Fiord, whose general trend is north northeast, has a total length of 24 miles, and varies in width from 2 to 8 miles, its walls being nearly everywhere precipitous. It has two indentations, both on the east side, the southernmost being a broad cove at the outlet of Coghill River 8 miles north of Port Wells, the second, Yale Arm, a tributary fiord 8 miles in length entering College Fiord 6 miles south of the head.
Harvard Glacier is at the head of College Fiord, Yale Glacier forms the head of Yale Arm. There are eight small cascading glaciers in the upper part of College Fiord, seven on the west side, and one on the east, and, of these, four descend the fiord wall to the water. In the lower part of College Fiord, there are five moderate-sized glaciers on the east side, including Dartmouth, Williams, Amherst, and Crescent Glaciers, all of which now end some distance back from the water. Beside these glaciers there are numerous